Phase I advanced the development of a prototype Rapid Test transdermal patch for the non-invasive screening detection of alcohol. The stability of the reagent components (alcohol oxidase; horseradish peroxidase; tetramethylbenzadine) on the cellulose membrane was improved. The kinetics and coupling of the enzyme/chromogen components were studied. The reactivity of the patch to relevant concentrations of alcohol in vitro was optimized. The Phase II project achieves final optimization of the detection pad and further evaluation of three different methods for applying the enzymes to the membrane (roller vat; drop; nebulizer spray). Stability of the Alcohol Rapid Test patch will be evaluated and the scale-up manufacturing process will be defined. The performance (sensitivity, specificity) of the Alcohol Rapid Test patch will be evaluated in a well-controlled clinical trial involving normal, healthy human volunteers. Phase II further proposes to extend the technology by establishing "proof-of-principle" for an Alcohol Abstinence Monitor, a transdermal alcohol patch that can remain on the subject's skin for up to seven days capable of detecting lower levels of alcohol, or deviations from an alcohol abstinence program. PROPOSED COMMERCIAL APPLICATIONS: The DSI alcohol patch addresses the needs of a $50 million alcohol testing market. The Rapid Test patch is a non-invasive, single step screening method for the detection of alcohol that is faster (results in 3 minutes or less), easier to use, can be performed on-site, and is more cost effective than existing multi-step methods. Medical applications include emergency rooms, hospitals and alcohol rehabilitation centers. Non-medical applications include workplace screening and the criminal justice system.